dnsmasq: abort dhcp_check on interface state

Abort the link-check based on the interface instead of the carrier
state. In cases where the interface is up but the carrier is down,
netifd won't case a dnsmasq reload, thus dhcp won't be active on thsi
interface.

Signed-off-by: David Bauer <mail@david-bauer.net>

package/network/services/dnsmasq/files/dnsmasq.init

@@ -106,9 +106,9 @@ dhcp_check() {
 
 	[ -s "$stamp" ] && return $(cat "$stamp")
 
-	# If there's no carrier yet, skip this interface.
+	# If interface is down, skip it.
 	# The init script will be called again once the link is up
-	case "$(devstatus "$ifname" | jsonfilter -e @.carrier)" in
+	case "$(devstatus "$ifname" | jsonfilter -e @.up)" in
 		false) return 1;;
 	esac